package leetcode.editor.cn;

import java.util.Arrays;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int n = scan.nextInt();
        int x = scan.nextInt();
        int y = scan.nextInt();
        int[] nums = new int[1010];
        for (int i = 0; i < n; i++) {
            int score = scan.nextInt();
            nums[score]++;
        }
        if (n>2*y){
            System.out.println(-1);
            return;
        }
        //最多选y人
        if (n>=y+x){
            System.out.println();
            for (int i = 0; i < nums.length; i++) {

            }
            return;
        }
        //最多选n-x
        if (n>=2*x){

            return;
        }
        System.out.println(-1);
    }
}
